The present invention relates to multipurpose hand tools, and in particular relates to such a tool having channel shaped handles which may be folded with respect to each other and other parts of the tool, providing a compact nested tool which permits certain blades to be opened into extended positions without unfolding the handles.
Applicant's assignee is the manufacturer of folding multipurpose tools similar to the tools disclosed in Leatherman U.S. Pat. No. 4,238,862 and Leatherman U.S. Pat. No. 4,744,272, as well as those described in pending U.S. patent applications Ser. Nos. 08/563,922 and 08/863,057, now U.S. Pat. Nos. 5,745,997 and 5,826,338. All of the above-mentioned tools manufactured by applicant's assignee include handles having the form of generally U-shaped channels. These handles fold around the bases of respective ones of a pair of pivotally interconnected jaws, thus housing the jaws within the channels, placing the tool in a compact form so it can be carried easily on one's person. Tool blades or bits, such as knife blades, screwdriver bits, and can openers, can also be stowed within the channel-shaped handles, and selected ones of these blades and bits can be extended individually for use. Extending a selected one of such blades or bits, however, requires that the handles be spread apart from one another while the selected blade is pivoted from its stowed position within the channel to its extended position. Thereafter, the handles should be replaced alongside each other to serve best as a handle for the selected blade.
When the pliers or other pivoted-jaw or pivoted-blade tool is used the handles are extended with respect to the bases of the pivotally interconnected jaws or blades. In this configuration the channels face openly outward, away from each other, with the channel bottoms of the handles facing toward each other. Depending upon the thickness of the material of which the channels are formed, the edges of the channel walls, thus facing outwardly, may be uncomfortable to one's hand when the handles are squeezed together during use of the pliers or similar tool.
While in some similar tools narrow strips along the edges of the channel walls have been folded inward to lie tightly alongside the walls and present a folded margin, this gives only a slight improvement in comfort and adds to the cost of manufacture.
It is desirable in a multipurpose folding tool for a blade or tool bit, particularly a knife blade, not to be able to fold unintentionally with respect to its handle during use. While springs and cams have been used previously to keep a selected blade or tool bit of a multipurpose folding tool in its extended position of use, it is desired to have a more positive way to keep such a blade or tool bit extended during use.
It is also desired to be able easily to open a selected one of a group of most commonly used blades. In some cases it is desirable to open such a blade without having to use more than one hand.
Not only should a multipurpose tool be capable of performing several different functions, the tool should be capable of being manufactured at a reasonable cost without sacrificing quality, as evidenced, for example, by smooth movement of individual blades between stowed and extended positions, and by reliable retention of blades in their operative positions during use.
What is desired, then, is an improved multipurpose folding tool offering easy access to certain blades and comfortable use of tools with a pair of pivotally interconnected jaws, such as pliers or shears, yet which is able to be manufactured with reliably high quality at a moderate cost.